Wednesday, February 14, 2018

Special Sewing Machines and Their Functions with Picture

Sewing machine is the basic element of garment making. It plays an important role in garments manufacturing industry. There are different types of sewing machine used in apparel industry. Generally single needle lockstitch machine and double needle lock stitch sewing machine widely used in sewing department. Without these some special sewing machines also used to complete garment. In this article I will give description of special types of important sewing machine those are frequently used in clothing manufacture.

Special Sewing Machines: Important and special; types of sewing machine list are given below.

Overlock Machine

Bar Tacking Machine

Buttonhole Sewing Machines

Button Sewing Machine

Feed of Arm Sewing Machine

Blind Stitch Machine

Overlock machine: It sews over the edge of the fabric plies for edge neatening, hemming or seaming. Generally, an overlock machine called a ‘sergers’ (Figure-1) will trim the fabric edges during sewing using cutters. The addition of automated cutters ensures these machines to produce a finished seam easily and quickly.

Figure-1: Overlock machine

It uses a bottom thread known as a looper thread fed by larger size cones compared to smaller size bobbins in the case of lock stitch machines. The loopers provide thread loops that pass from the needle thread to the fabric edges thereby raw edges are enclosed within the seam. Overlock sewing machines are normally run at high speeds, from 1000 to 9000 rpm.

Bar tacking machine: The bar tack machine shown in Figure-2 is used for sewing dense tack around the open end of the buttonhole. These machines are used to make more tight stitches across the point to be reinforced and then sew covering stitches at a right angle over the first stitches.

Figure-2: Bartack machine

Figure-3: Application of bartacking machine

The applications of the bar tack machine in the garment industry are given below:

Closing of buttonhole end.

Reinforcing the ends of pocket opening.

Sewing on belt loops.

Buttonhole sewing machines: Buttonhole machines are used for creating buttonholes in the garment and to finish the edges. A buttonhole machine as shown in Figure-4 may form a simple circle where the stitches radiate from the centre of an eyelet home, two legs on either side of a straight out with a bar tack on both ends as in a shirt, a continuous line of sewing up one leg, round the end and down the other without the cut as in a shank.

Figure-4: Buttonhole sewing machine

The selection between lock stitch and chain stitch is based on seam security requirements and the requirements of edge finishing. In general, a buttonhole on a tailor outward utilities two thread chain stitches; the chain affect gives an attractive purl appearance to the buttonhole. The simpler shape of a buttonhole on shirts and other lightweight garments is frequently used with a single thread chain stitch and in some cases the sewing is done inside the garment.

Buttonhole machine types: The buttonhole sewing machines are categorised based on the following:

1. Stitch type such as lock stitch or chain stitch machines 2. Size and shape of the buttonhole 3. Method of creating buttonholes

Button hole cut before stitch – The button hole is cut first and then finished with stitches. The stitches radiate from the center to the outer edge of the buttonhole. It gives a neat appearance as the sewing thread covers raw edges of the hole effectively.

Button hole cut after stitch – As the name indicates, the buttonhole edges are finished first and then slashed. It is created by a continuous line of sewing around the end and then the hole is cut subsequently.

4. Presence or absence of gimp

Button sewing machine: A button sewing machine (Figure-5) is used to sew the button in the garment without damaging it. Various types of buttons like a button with two holes, four holes or shank could be sewn on this machine by making simple adjustments. The sewing action comprises a series of parallel stitches whose length is equal to the distance between the centres of the holes. The needle has only vertical movement but the button moves sideways by means of the button clamp for stitching. A hopper feed is a special attachment that automatically feeds the button to the clamp of the needle point of the machine. With this attachment, the button and needle are automatically positioned and the threads are clipped.

Figure-5: Button sewing machine.

Feed of arm sewing machine: It is used to stitch a tubular seam of narrow width on the edge of shirts and trousers (Figure-6). It is particularly utilized for sewing a lapped seam which has to be closed such that the garment panels become a tube-like structure. These machines are common for sewing outside leg seams in jeans where the lap felled seam is used.

Figure-6: Feed of arm sewing machine.

Blind stitch machine: A blind stitch machine (Figure-7) is used for hem stitching in a knitted fabric since the hem stitch is too small in the right side of the garment and is invisible. In a few circumstances, the machine could be set to skip a stitch that is to pick up the fabric on alternate stitches only. But this type reduces the stability of the stitches.

Figure-7: Blind stitching machine.

The sewing needle utilised for this machine is a curved one because it does not pierce through the fabric fully, but partially. Based on the application and type of fabric, the blind stitch can be grouped into two types; for fine fabric producing long and narrow stitches and for heavy fabric with short and wide stitches.